Application of accelerated rehabilitation surgery concept in laparoscopic radical gastrectomy cancer for patients aged ≥ 70 years

Background: To explore the application effect of accelerated rehabilitation surgery on laparoscopic radical gastrectomy cancer for patients aged ≥ 70 years. Methods: Retrospective analysis of 120 aged ≥ 70 patients’ clinical data undergoing laparoscopic radical gastrectomy in our hospital from January 2017 to December 2018, which were divided into accelerated rehabilitation group (n = 73) and control group (n = 47). By comparing the postoperative clinical data of the two groups, we explored the application effect of accelerated rehabilitation surgery on laparoscopic radical gastrectomy cancer for patients aged ≥ 70 years. Results: Compared with the control group, the rst time to get out of bed (2.1 ± 0.9 days vs 3.8 ± 1.5 days, P<0.01), the rst exhaust time (3.2 ± 0.8 days vs 3.9 ± 1.2 days, P<0.01) and the rst time to eat liquid food after surgery (1.8 ± 0.9 days vs 3.2 ± 1.3 days, P<0.01), and postoperative hospital stay (12.7 ± 4.3 days vs 15.8 ± 6.4 days, P<0.01) in the rehabilitation group were signicantly lower. There was no signicant difference in the overall postoperative complications between the two groups (P<0.05), however, the complications of pulmonary infection in the accelerated rehabilitation group was signicantly lower than that in the control group (1.4% vs 10.6%, P = 0.03). Conclusions: The application of accelerated rehabilitation surgery concepts and measures after surgery in laparoscopic radical gastrectomy cancer for patients aged ≥ 70 years can promote early postoperative rehabilitation, reduce postoperative hospital stay, and reduce the incidence of postoperative pulmonary infection complications. few reports about the ERAS in laparoscopic gastric cancer surgery for elderly patients. With the rapid development of surgical technology and the promotion of the concept and measures of ERAS, it is signicant to analyze the inuences of ERAS in the perioperative period of laparoscopic gastric cancer surgery for elderly patients. This study aims to investigate the effect of accelerated rehabilitation surgery on laparoscopic radical gastrectomy cancer in patients aged ≥ 70 years.

however, the complications of pulmonary infection in the accelerated rehabilitation group was signi cantly lower than that in the control group (1.4% vs 10.6%, P = 0.03).
Conclusions: The application of accelerated rehabilitation surgery concepts and measures after surgery in laparoscopic radical gastrectomy cancer for patients aged ≥70 years can promote early postoperative rehabilitation, reduce postoperative hospital stay, and reduce the incidence of postoperative pulmonary infection complications.

Background
Enhanced recovery after surgery (ERAS) refers to multi-modal management during perioperative period, reducing the patient's surgical stress response and complications, and facilitating recovery, which is currently relatively mature in colorectal surgery [1,2]. In recent years, ERAS is claimed to be safe and feasible in gastric cancer surgery, and well promoted in the research [3][4][5]. However, there is few reports about the ERAS in laparoscopic gastric cancer surgery for elderly patients. With the rapid development of surgical technology and the promotion of the concept and measures of ERAS, it is signi cant to analyze the in uences of ERAS in the perioperative period of laparoscopic gastric cancer surgery for elderly patients. This study aims to investigate the effect of accelerated rehabilitation surgery on laparoscopic radical gastrectomy cancer in patients aged ≥70 years.

General information
In the study, we collected the clinical data of 120 patients aged ≥70 years with laparoscopic radical gastrectomy in Department of Gastrointestinal and Pancreatic Surgery, Zhejiang People's Hospital from January 2017 to December 2008. Patients were divided into two groups, ERAS group and control group.
The clinical data included age, gender, body mass index (BMI), preoperative comorbidity, American Society of Anesthesiologists (ASA) classi cation, surgical procedure, reconstruction mode, operative time, intraoperative blood loss, number of lymph nodes, and cancer staging.

Inclusion and Exclusion
Inclusion criteria: 1) age of patients ≥ 70 years, 2) patients could adopt laparoscopic radical gastrectomy by preoperative assessment, 3) patients were con rmed as gastrectomy cancer by postoperative pathology, 4) patient informed consent, 5) patient undergo laparoscopic radical gastrectomy, 6) clinical data intact, 7) patient had no distant metastasis.
Exclusion criteria: 1) patients with severe cardiopulmonary disease could not tolerate laparoscopic surgery; 2) patients were transferred to open surgery, 3) tumor invaded adjacent organs and was accepted expand resection, 4) patient had distant organ metastasis.

Observation indicators and discharge criteria
The time of rst post-operative activity, eat liquid food after surgery, anal recovery exhaust time, postoperative complications and postoperative hospital stay were observed. The discharge criteria of the two groups are the same: eating semi-liquid without discomfort and without intravenous rehydration, defecation is normal, pain is under control, movement is free, and abdominal drainage tube has been pulled out.

Statistical methods
Data analysis was performed using SPSS.20 statistical software. Continuous variables were expressed as mean ± SD, and t-tests were used for comparison between two groups. The categorical variable is expressed as a percentage, using the chi-square test. The signi cant difference is expressed by P<0.05.

Results
The comparison of general data before surgery and management measures during surgery The general data of the two groups of patients was extracted, including age, BMI, American Society of Anesthesiologists (ASA) score, comorbidity, tumor stage, surgical method, reconstruction method, operation time, amount of bleeding and number of lymph node dissections. There was no signi cant difference of these data between the two groups (Table 1). The perioperative management measures were also collected ( Table 2). Drink a small amount of water on the first day after surgery, and a liquid diet on the second and third days, and gradually transition to a semi-liquid diet.
Anal venting, water intake after gastrointestinal tube removal The comparison of clinical data after surgery Laparoscopic surgery was successfully performed in both groups. Compared with the control group, the time to rst get out of bed, the rst time to eat liquid food after surgery, the postoperative anal recovery time, and the postoperative hospital stay were lower in the accelerated rehabilitation group (P<0.05). There was no signi cant difference in the overall complication rate between the two groups (P>0.05), but the postoperative pulmonary infection rate in the accelerated rehabilitation group was signi cantly lower than that in the control group (1.4% vs 10.6%, P<0.05). One patient died in the perioperative period, and the difference was not statistically signi cant (P>0.05). See Table 3 for details.

Discussion
Gastric cancer is one of the most common malignant tumors in China, and Surgery is the only radical approach. As aging has become a social problem, the number of elderly patients with gastric cancer is also increasing. However, due to cardiopulmonary complications increasing, physical function declining, relatively low immunity, and malnutrition of elderly patients, postoperative complications will be increased and recovery will be slow after abdominal surgery [6,7]. Therefore, it is a hot topic in clinical research on how to promote the rapid recovery of laparoscopic radical gastrectomy cancer for elderly patients.
ERAS was rst proposed by Kehlet, a Danish scholar. It adopts a series of evidence-based medical management measures to reduce the patient's surgical stress and postoperative complications effectively, and promote patient's rehabilitation. The optimization management measures include preoperative education, intraoperative warming, early post-extubation, early getting out of bed, early eating after surgery and so on [8]. EARS is widely promoted and proves to have following characteristics shorten postoperative hospital stay after surgery, reduce postoperative complications, ease pain and improve postoperative recovery [8,9]. In this study, the time for the rst time to get out of bed in the accelerated rehabilitation group, postoperative liquid food intake time, and the anal recovery exhaust time were signi cantly lower than those in the control group; the postoperative hospital stay was also signi cantly lower than that in the control group, which is consistent with the results reported in the literature [4,10].
For elderly patients, most surgeons prefer to adopt conservative treatments during perioperative management. In order to prevent aspiration during anesthesia and surgery, patients require long time fasting before surgery. However, some studies [11]show that long period fasting will cause hunger, anxiety and energy consumption of the body, which easily disorders patient's internal environment, reduces their stress ability, and decreases resistance and immunity.  [5] research. The main reason should be ERAS group does not perform bowel preparation before surgery, which ensures the normal intestinal ora and reduces the postoperative in ammatory response. The ERAS group also has early postoperative intake, which reduces digestive juice loss, avoids uid and electrolyte disorders, and enhances the intestinal function recovery. In traditional concept, gastrointestinal tract will be paralyzed after surgery, so indwelling gastric tube should be placed to observe and reduce postoperative complications. But most of elderly patients have cardiopulmonary complications, in that case indwelling gastric tube may cause sputum blockage and lung infection. Besides, indwelling gastric tube restricts patient's activity, and then increases the risk of deep venous thrombosis. In this study, the incidence of lung infection of ERAS group is obviously lower than Control group (1.4% vs 10.6%, P=0.03). Nonindwelling gastric tube for ERAS group is one of the reasons, and the other one is the group will organize a series of activities for elderly patients, like ERAS conception propaganda before surgery, respiratory function exercise, routine atomization inhalation, back patting after operation, encouraging patients to get out of bed earlier, cough and expectoration.

Conclusions
In summary, the application of ERAS concepts and measures during the perioperative period of laparoscopic radical gastrectomy cancer for patients aged ≥70 years can not only promote rapid postoperative recovery, reduce postoperative hospital stay, but also reduce postoperative incidence of lung infection. The concept and measures are worthy of application and promotion in elderly patients undergoing laparoscopic radical gastrectomy cancer. Of course, this study is a retrospective study. It is inevitable that there is selection bias. The analgesic effect of postoperative patients and the improvement of anesthesia during the operation have not been studied. These will be the directions for further research.

Consent for publication
All subjects have written informed consent.

Availability of data and materials
The authors declare that all relevant data supporting the nding of this study are available within the paper. All data are available from the corresponding author on reasonable request.

Competing interests
The author had no con ict of interest in relation to this study.

Funding
This work was supported by Natural Science Foundation of Zhejiang Province (LY20H160045, LQ20H200004, LY20H080009) and Zhejiang Medical and Health Science and Technology Program (2020RC021, 2020KY015, 2018KY243). The funder had no role in the process of study design, data analysis, decision to publish or preparation of manuscript.

Author Contributions
Jun Ma designed the study and wrote the manuscript; Hongliang Shao collected the data; Yanzhong Wang analyzed the data; Yirui Chen reviewed and edited the manuscript; Yiping Mou conceived and designed the study. All authors read and approved the manuscript.